For certain Internet applications, resources are reserved to achieve the necessary quality of service (QOS). The reservation of resources allows packet based networks to operate like circuit switched networks. FIG. 1 is an illustration of a simplified wireless packet based, such as Internet based, communication session, such as for wireless Internet, wireless multimedia, voice over Internet Protocol, video conferencing or video telephony, between two wireless users, user A and user B. Differing sessions have differing performance requirements, such as setup time, delay, reliability, integrity and quality of service (QOS). User A is shown as user equipment (UE) 20 and user B is shown as UE 22. User A sends and receives communicates via the packet network 28 using its cellular network 24. User B similarly sends and receives communications via the packet network 28 using its cellular network 26.
FIG. 2 is an illustration of establishing such a session. User A sends a resource reservation setup protocol (RSVP) PATH message 30 to establish the session. The RSVP PATH message 30 is sent to user B via various network routers (Router 1-Router N). Each router determines whether the resources are available for the session. If adequate resources are available, the RSVP PATH message 30 is updated and passed to the next router. If adequate resources are not available, an error message is sent back to user A. When user B receives the RSVP PATH message 30, user B responds by sending a RSVP reservation (RESV) message 32 to reserve the resources throughout the networks 24, 26, 28. As the RSVP RESV message 32 is sent through the networks, resources are allocated to support the communications from user A to user B. If the resources are successfully allocated, user A receives the RSVP RESV message 32. User A sends a confirmation (RSVP confirm) message 34 to user B to acknowledge receipt of the RSVP RESV message 32.
To allocate resources for user B′s communications to user A, user B sends a RSVP PATH message 30 to user A via various network routers (Router 1-Router N). When user A receives the RSVP PATH message 30, user A responds by sending a RSVP RESV message 32 to reserve the resources throughout the networks 24, 26, 28. As the RSVP RESV message 32 is sent through the networks 24, 26, 28, resources are allocated to support the communications from user B to user A. If the resources are successfully allocated, user B receives the RESV message 32. User B sends a RSVP confirm message 34 to user A to acknowledge receipt of the RSVP RESV message 34.
To maintain the resource allocations, Refresh PATH messages 36 are periodically sent through the networks 24, 26, 28. User A sends Refresh PATH messages 36 through the networks 24, 26, 28 to user B to maintain the resources for user A's transmissions and user B sends Refresh PATH messages 36 through the networks 24, 26, 28 to user A to maintain the resources for user B's transmissions. If the Refresh PATH messages 36 are not sent, the reservation states will expire with the allocated resources being released.
Sending all these messages to allocate resources uses valuable network resources. Accordingly, it is desirable to have alternate approaches to establishing wireless Internet sessions.